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The lacrimal glands are paired almond-shaped glands, one for each eye, that secrete the aqueous layer of the tear film. They are situated in the upper, outer portion of each orbit, in the lacrimal fossa of the orbit formed by the frontal bone.〔(Clinically Oriented Anatomy ), Moore, Dalley & Agur.〕 Inflammation of the lacrimal glands is called dacryoadenitis. The lacrimal gland produces tears which then flow into canals that lead to the lacrimal sac. From this sac, the tears drain through the lacrimal duct into the nose. Anatomists divide the gland into two sections. The smaller ''palpebral portion'' lies close to the eye, along the inner surface of the eyelid; if the upper eyelid is everted, the palpebral portion can be seen. The orbital portion contains fine interlobular ducts that unite to form 3–5 main excretory ducts, joining 5–7 ducts in the palpebral portion before the secreted fluid may enter on the surface of the eye. Tears secreted collect in the fornix conjunctiva of the upper lid, and pass over the eye surface to the lacrimal puncta, small holes found at the inner corner of the eyelids. These pass the tears through the lacrimal canaliculi on to the lacrimal sac, in turn to the nasolacrimal duct, which dumps them out into the nose.〔"eye, human."Encyclopædia Britannica. 2010. Encyclopædia Britannica 2010 Ultimate Reference Suite DVD 2010〕 ==Microanatomy== The lacrimal gland is a compound tubuloacinar gland, it is made up of many lobules separated by connective tissue, each lobule contains many acini. The acini contain only serous cells and produce a watery serous secretion. Each acinus consists of a grape-like mass of ''lacrimal gland cells'' with their apices pointed to a central lumen. The central lumen of many of the units converge to form intralobular ducts, and then unite to from interlobular ducts. The gland lacks striated ducts. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lacrimal gland」の詳細全文を読む スポンサード リンク
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